LAUSR

1.3- $\mu \text{m}$ high-speed directly modulated lasers (DMLs) based on high-order slotted surface gratings are proposed. The time-domain travelling-wave model combined with the 2-D scattering matrix method is employed for the analysis of the proposed DMLs. By optimization an intrinsic direct-modulation bandwidth up to 33 GHz has been predicted for a 250- $\mu \text{m}$ -long laser with a threshold current of about 4 mA and a slope efficiency of about 0.4 mW/mA. Such lasers are regrowth free and have strong potential to realize low-cost high-reliability DMLs.